Why a Diamond Looks Cloudy and How to Fix It

A diamond that once sparkled now looks flat. It is a common worry, and the cause is usually simple.

The most common cause: dirt and grease

Diamonds attract oil. Skin oils, lotion, soap and dust build a thin film over the surface and underneath the stone, where the setting is open. The film stops light entering and leaving, so the diamond looks dull or cloudy. Nothing is wrong with the stone itself.

The fix

Clean it gently. See how to clean diamond jewellery at home. Soak in warm soapy water, brush the underside as well as the top and rinse well. For many cloudy diamonds, this restores the sparkle at once.

If cleaning does not help

Look for other causes.

The setting is dirty underneath

In some settings, dirt packs into the space under the stone and is hard to remove. A jeweller can clean it with a steam cleaner or an ultrasonic cleaner, where it is safe for the piece.

A residue that soap does not remove

Some products leave a stubborn film. A jeweller can use stronger methods safely.

The metal is dull

If the metal looks dull but the stone is fine, the surface of the metal may need polishing.

Scratches or wear on the stone

A diamond is very hard, so scratches are rare, but facets can become worn on stones that have been knocked or rubbed by other diamonds. A jeweller can examine it under magnification. See are diamonds unbreakable?.

The stone itself

Some diamonds have a hazy or milky look because of their internal structure, for example many tiny inclusions, or strong fluorescence that makes them look slightly oily in some lights. This was there from the start. See diamond inclusions explained and diamond fluorescence explained.

It is not a diamond

A stone that looks cloudy and does not respond to cleaning may be a different material. A jeweller can test it. See how to spot a fake diamond.

Prevention

• Put jewellery on after cosmetics. See perfume, lotion and jewellery: what to avoid.
• Wipe pieces after wearing.
• Clean regularly, every week or two for daily pieces.
• Have a professional clean once or twice a year.

When to see a jeweller

If a clean does not restore sparkle, if you see chips or if a stone looks loose, take it to a jeweller. They can tell you whether it is dirt, wear or something else.

Common questions

Can a cloudy diamond become clear again? If the cloudiness is dirt, yes.

Can I use toothpaste? No. It is abrasive and can scratch the metal.

Do diamonds lose their sparkle over time? The stone does not. Dirt, wear on the metal and loose settings affect how it looks.

How to tell dirt from a stone issue

Clean the piece properly, dry it and look at it again in daylight. If the sparkle returns, it was dirt. If a hazy look remains in the same place when you tilt the stone, it is probably inside the stone and was always there. If it looks dull all over, suspect a worn or dirty setting, or a stone that is not a diamond. A jeweller with a loupe can answer the question in a minute, and it is worth asking before you spend money on cleaning products.

Get a professional clean

At our showroom, cleaning and inspection is part of our service. Book an appointment, or browse our diamond rings and earrings.